Tutorial by Examples: er

public final class Color { final private int red; final private int green; final private int blue; private void check(int red, int green, int blue) { if (red < 0 || red > 255 || green < 0 || green > 255 || blue < 0 || blue > 255) { throw ...

In this case class Point is mutable and some user can modify state of object of this class. class Point { private int x, y; public Point(int x, int y) { this.x = x; this.y = y; } public int getX() { return x; } public void setX(int ...

Suppose we have this file: test>>cat file 10.Gryffindor 4.Hogwarts 2.Harry 3.Dumbledore 1.The sorting hat To sort this file numerically, use sort with -n option: test>>sort -n file This should sort the file as below: 1.The sorting hat 2.Harry 3.Dumbledore 4.Hogwa...

Since BackAndroid is deprecated. Use BackHandler instead of BackAndroid. import { BackHandler } from 'react-native'; {...} ComponentWillMount(){ BackHandler.addEventListener('hardwareBackPress',()=>{ if (!this.onMainScreen()) { this.goBack(); return true; ...

Lets have the following file called library.cmd : @echo off echo -/-/- Batch Functions Library -/-/- :function1 echo argument1 - %1 goto :eof To execute only the :function1 without the code of the rest of the file you should put a label :function1 in the caller bat and use it lik...

import java.util.StringTokenizer; public class Simple{ public static void main(String args[]){ StringTokenizer st = new StringTokenizer("apple ball cat dog"," "); while (st.hasMoreTokens()) { System.out.println(st.nextToken()); } } ...

public static void main(String args[]) { StringTokenizer st = new StringTokenizer("apple,ball cat,dog", ","); while (st.hasMoreTokens()) { System.out.println(st.nextToken()); } } Output: apple ball cat dog

Parent element html <child-component [isSelected]="inputPropValue"></child-component> Parent element ts export class AppComponent { inputPropValue: true } Child component ts: export class ChildComponent { @Input() inputPropValue = false; } Child compone...

The "Host:" header is a normal way an HTTP client tells the HTTP server which server it speaks to. By passing custom modified "Host:" header you can have the server respond with the content of the site, even if you didn't actually connect to the host name. For example, if you ha...

from django.contrib.auth.models import User class UserAdmin(admin.ModelAdmin): list_display = ('email', 'first_name', 'last_name') list_filter = ('is_staff', 'is_superuser') admin.site.unregister(User) admin.site.register(User, UserAdmin) We need to unregister before regis...

I wrote a simple C code foo.c int main() { int i = 0; int j = 0; for (i = 0; i < 5; i++) { j = i + 1; } return 0; } When compiled with -O0 i.e. by disabling all compiler optimizations $ gcc -o foo.S foo.c -O0 -S I got this: .file "foo.c&...

hello_world.c #include <linux/module.h> #include <linux/kernel.h> #include <linux/init.h> #define AUTHOR "Bruce Lee" #define DESC "Hello World driver" static int __init init(void) { printk(KERN_DEBUG "Hello World\n"); return 0;...

var foo : Int by Delegates.observable("1") { property, oldValue, newValue -> println("${property.name} was changed from $oldValue to $newValue") } foo = 2 The example prints foo was changed from 1 to 2

val map = mapOf("foo" to 1) val foo : String by map println(foo) The example prints 1

interface Foo { fun example() } class Bar { fun example() { println("Hello, world!") } } class Baz(b : Bar) : Foo by b Baz(Bar()).example() The example prints Hello, world!

Heroku will always pass on a X-Request-ID header send by the client, or generate its own. See documentation at HTTP Request IDs.

All of the other buttons you can create, are buttons that link to a GitHub repository and prompts the user to complete a certain action. These buttons can do actions such as: Watch a repository Star a repository Fork a repository Download a repository List an Issue with a repository Here's...

The cluster module allows one to start the same application multiple times. Clustering is desirable when the different instances have the same flow of execution and don't depend on one another. In this scenario, you have one master that can start forks and the forks (or children). The children work...

A typical example of the implementation of a Looper thread given by the official documentation uses Looper.prepare() and Looper.loop() and associates a Handler with the loop between these calls. class LooperThread extends Thread { public Handler mHandler; public void run() { Lo...

A HandlerThread can be used to start a thread with a Looper. This looper then can be used to create a Handler for communications with it. HandlerThread thread = new HandlerThread("thread-name"); thread.start(); Handler handler = new Handler(thread.getLooper());